Tone-purifier for talking-machines.



C. P. MARSHALL.

TONE PURIFIER FOR TALKING MACHINES. APPucAnoN'mEu Aus.31'.1915.

1 1 99, 1 97. Paton-ted Sept. 26, 1916.

CHARLES P. MARSHALL, OF WATERTOWN, NEW YAOBK..

TONE-PURIFIER FOR, TALKING-MACHINES.

Speeication of Letters Patent.

Patented sept. 2e, 1916.

Application filed August 31, 1915. Serial No. 48,320.

To all whom it may concern:

Be it known that I, CHARLES P. MARSHALL, a citizen of the United States, residing at Watertown, in--the county of Jefferson and State of New York, have invented certain new and useful Improvements in Tone- Puriiiers for Talking-Machines, of which the following is a specification.

This invention relates to means for purifying the tones of phonographs, talking-machines, and like musical instruments, and the invention relates particularly to a combined tone purifier comprising a damping device for attachment to the vibration bar, and a bell for partially or wholly 'covering orinclosing the reproducer, of such instru-' ments.

` The object of the invention is to improve the quality of the tones of talking-machines, phonographs and the like, and to render them clearer, truer, purer and more natural than heretofore. v

A particular object of the invention is to improve the means shown and described in my pending application, Serial No. 22709, filed April 20, 1915.

The'various features and parts of the invention will be understood from the detailed description which follows, and by reference to the accompanying drawing which forms a part of the specification, in which- Figure l is an elevational view of the reproducing parts of a talking-machine; showing my combined tone purifier applied thereto. Fig. 2 is an enlarged elevational view; partially in section, of the same. Fig. 3 is an enlarged view of one form of the damping part, which is applied to the vibrationbar of the reproducer. Fig. 4 is a perspective view; showing a modified form of the damping part. Fig. 5is an elevational view, partially in section; showing the bell applied to the back of thetransmitter. Fig. -6 is a modified view of the bell. Fig. 7 is still another modified view of the bell. Fig. 8 is another detailed view of the rubber damping part. Fig. 9 is a view of a modified form of the damping part.

In the drawing, 2 represents'the hollow case of the reproducer. or transmitter, in

which is disposed the usual diaphragm 3,

the latter being held in place by a ring-cap 4. The reproducer is mounted upon the usual hollow sound-arm 5, which is sup` ported by thebox or cabinet 6.

7 represents the revolving support for the record disk 8, the former being rotatably mounted upon the cabinet 6 in the usual manner.

My tone modifiers or purifiers relate entirely to attachments which are applied to the reproducers of talking-machines of varlous klnds, and comprise two parts, A and B, which coperate for subduing the discordant noise of the fundamental note of the diaphragm, and also of the vibrationbar, and at the same time, adding a new tone to the reproducer, which tends to cover up the excess of the said noises not'otherwise subdued. The noises referred to, it may be explained, are not a part of the music transmitted from the record, but are harsh and gratlng notes which are given off by the diaphragm land vibration-bar, when these parts are vibrated` by the contact of the needle with the revolving record-disk.

The part A consists of a piece of rubber or other suitable material, preferably soft and flexible, like the material of an eraser or rubber band, which is preferably forked, as shown in Figs. 2 and 8. The free ends of the arms (zare slotted, as at 9, to receive or straddle the vibration-bar 10, or preferably that portion of the said bar, which extends between the elbow 11 and' a shoulder 12 of the support 13 which holds the needle 13.

Fig. 8 shows the rubber part A before it is' of weight required.

The part A is held upon the vibration-bar* solid or hollow, according to the amount by means of screws or bolts 17, which pierce the slotted ends of the arms a. The rubber part may be made to different forms, -and 1 may be applied to the vibration-bar in various ways, and may or may not have lassociated with it, the pins and balls, 15 and 16, as shown in Figs. 4 and 9. By disposing the part A said part being like substance, tends to'damp or lessen the amplitude of the vibrations of the said bar,

upon the vibrationbar,'tle comprised of soft rubber, or A and ,also subdues any vibratory noise which maybe produced by said bar. The length of the part A, as well as the spacing 4 of its arms, and also the contact of said arms with the different portions of the vibrationbar, all tend torestrict the vibrations, and also to subdue 'the noise, of said bar, to a greater or lesser extent, and in practice the operator may readily and quickly shift the Y partA .from one position to another for the cap 4 of the reproducer are transmitted altering, or effecting, the different 4degrees of modification referred to. The ball 16 and its supporting rod .1.5 both contribute to the subduing effect 'of' the part A Yupon the vibration-bar, and 'its presence or absence can be noticed by a quick ear. The part A does not in any way hinder the bar 10 from performing its intended work, 11. e. transmitting the vibrations from the needle 13 to the diaphragm 3. The part A, owing to its size, weight and non-vibrative nature, re-

stricts the amplitude of the vibrations of pierced by screws 19, the inner ends Vof the screws extending beyond and engaging the underside of the over-hanging Hange 4 of the cap. Various other fastening means mav be employed instead of the partsshown 1n Figs. 2 and 5. The smaller end b of the bell is preferably closed. In the preferred form of the bell,- one side, as b is flattened so' as to leave a portion of the diaphragm 3 exposed. and also to form an auxiliary diaphragm (see Figs. 1 and 2).. The bell B completely incloses or houses inthe vibration-Dar and the rider A.

In operation the -vibrations of the rim of f tothe bell, causing the latter to resound with its own tone or tones, and the latter are taken up to a' greater or less extent by the diaphragm and are heard in the nusic'or y reproductionfrom the record. In this way a pleasing tone quality is added to the re'- production, which isv rendered still more pleasing to the ear, because the noises from the flmdamental notes of the diaphragm and vibration-bar -are practically overcome or covered-up. A difference in the size, weight and material yo f the bell correspondingly' enhances this pleasing effeet. The bells B may be made up-in many different forms, and may be provided with various tone modifying features, as forexample, the slots 20, the perforations 21,and

the notches 22, as shown inJFig. 6, as welll as by Stringing Wires across the interior of the bell, as shown at 23 in Fig. 7. The

bell may also be applied to Lthe back of the transmitter, or case 2, as shown at 24 in Fig. 5, for producing a still di'erent modified effect. In Fig. '5 the bell A has a slot 25 in its flat side to receive the sound-tube 5, an it is held in place by the lugs 18 and screws 19.

The rubber part A reduces the amplitude of the vibrations of the bar 10, steadying the latter, and subduing more or less the harsh noise of the said bar, which 'tends tomodify or purify the tone of the instrument, and render'music more pleasing, and

`speech and songs clearer and more distinct.

The part B by materially overcoming or l subduing the noise of the diaphragm as described acts in conjunction with the part A, and by reason of its individual tone re2 ferred to, adds mellowness, richness and brilliancy, according to its size, shape and substance, whichygreatlyfimproves the general tone of thel" instrument as compared with what has heretofore been accomplished.

In Fig. 4 I 'have shown a modified damping part, comprising a plain fiat strip of rubber 26, the opposite ends of which are slotted for straddling the lvibration-bar 10 `adjacent the shoulder 12 and also between.

the elbow 11 and the diaphragm 3. v'Ihe curved ends of the part 26 are held in position by bolts orvpins 27. By this disposition and arrangement -of thev part 26, the amplitude of the vibrations of the bar 10 is greater, and the tone of ther instrument is less smooth and clear, than in Fig. 2. This part is applicable to short types `of bells.

Fig. 9 illustrates a modied form of the lelastic damping part, which consists of an elongated body preferably extending nearly the full length ofthe vibration bar 10 and having a plurality of feet or legs resembling a centipede, which are slotted to receive and grip the.l said bar at frequent intervals be tween the 'elbow 11 and the shoulder of part 12. By the use of this damping part,

thevibration bar is divided into -a number of relatively short free orexposed portionsA which extend between the legs and these portions vibrate somewhat freely, but owlic ing to the .comparatively close spacing of the i legs, the amphtude of the vibrations is not very great and therefore offers little disv turbance during the reproductions.

Having thus described my. invention,

what Iclaim as new;` and desire to secure by Letters Patent, is

1. The combination of atalking machine having a diaphragm, a vibration-bar, an

open casing for supporting said parts, and an open bell mounted upon the face of said casing and covering said diaphragm and said bar, and means for securing saidbell with the rim of said casing.

2; In a tone modifier for talking machines, the combination withthe diaphragm and its supporting case, said case having an 'open face surrounded by an annular iange,l of a bell adapted to be mounted upon said annular flange and overlying said diaphragm, one end of said bell having a clear opening facing the diaphragm, and means for securing said bell to said flange. i

3. In a tone modifier, the combination with the, diaphragm and its supporting case, said casing having an annular portion ex` tending beyond the diaphragm, of a hollow truncated cone having one open end and one closed end adapted to be mounted upon the annular portion of said casing and overlying said diaphragm, the open end of said cone facing the diaphragm and one side thereof attened for exposing a portion of the diaphragm.

4. In a tone purii'er, the combination with the reproducer of la talking machine y comprising thelopen casing, the diaphragm,

and the vibration-bar, of a hollow truncated cone mounted; upon the open face of the casing, inclosing said vibration-bar and partially covering said diaphragm, the end of said coneacmg the diaphragm having a clear opening, and means comprising a plurality of lugs andscrews for .securing said cone to the casing.

5. A tone purifier or talking machines,

comprising a bell-shaped resonator having a clear open mouth mounted over the face of 6. A tone .purifier `for talkingmachines,

comprising a hollow. truncated cone mounted i upon the frame of the reproducerand partially\ concealing the reproducing diaphra the said cone having a-clear open- 1n acing the diaphragm and having onel flat side which acts as a sounding-board for modifying the noise of thediaphragm. 7. A tone purifier for talking machines, comprising a hollow resonator mounted upon the re roducing transmitter and partially overying the exposed face of the reproducing .diaphragm for subduing the noise of the said diaphragm, said resonator having an open end facing the diaphragm and having one flat side which acts as a sounding-board.

8. Asound rectifier for talking machines,

comprising a hollow bell-shaped 'resonator j having one open end, the opening 'in said end being unrestricted, said open end closely contacting with the rim of the reproducing transmitter and inclosing the diaphragm and also the vibration-bar which vibrates the said diaphragm, the said resonator` having one flat side which acts as an auxiliary sounding-board, and means engagingsaid rim for holding the resonator in place.

In testimony whereof I aiix my si ature.

' CHARLES P. MARS LL. 

